Textile material



Patented Oct. 22, 1940 UNITED STATES TEXTILE MATERIAL Angus Smith Belland Joseph Rowland Wyldc,

Spondon, near Derby, England, assignors to Celanese Corporation ofAmerica, a corporation of Delaware No Drawing. Application April 5,1938, Serial No.

4 Claims.

This invention relates to improvements in textile materials, and is moreparticularly concerned with new composite yarns and with fabrics orother materials made of or containing such yarns.

In recent years considerable research has been directed to theproduction, from artificial textile materials, of yarns which bear aresemblance to natural wool yarns. It has been found that yarns whichcontain short fibres of artificial textile materials, 1. e., artificialstaple fibres, are of con siderable value in this connection. Such yarnsmay be made by spinning, in a way comparable to cotton spinning, aroving containing artil5 ficial staple fibres, or may be made byprocesses which comprise treating a bundle of continuous filaments ofartificial material so that at least some of such filaments are brokenthough the continuity of the bundle as a whole is re- 20 tained.Processes of this latter type are described in U. S. Patents Nos.2,077,078 and 2,077,- 079.

It has now been discovered that very valuable compositeyarns, having agood resemblance to 3 W001 yarns, may be obtained by associating one ormore yarns containing artificial staple fibres with one or more yarnswhich after such association, are capable of being shrunk relative tosaid yarns containing artificial staple fibres, and 80 thereaftershrinking such shrinkable yarns.

The association of the yarns to form the composite yarns of the presentinvention may be brought about in any convenient manner. For example thedifferent yarns may be sized to- 35 gether so that they act thereafteras a single yarn until the finished woven fabric or other material isscoured to remove the size. However, it is preferable to bring about theassociation of the different yarns in the composite o yarn by a doublingtwist, preferably a light doubling twist.

The staple fibre yarns may have a basis of any artificial material.Thus, they may contain staple fibres having a basis of cellulose acetate5 or other organic derivatives of cellulose or staple fibres having abasis of regenerated cellulose and produced, for example, by theviscose, cuprammonium or nitrocellulose processes. Or again, the staplefibre yarns may contain staple fibres 50 which have a basis of celluloseacetate or other organic ester of cellulose and which have beenpartially or completely saponified, or staple fibres which have a basisof an organic derivative of cellulose and which have been subjected toesterii ficatlon, e. g. by the processes of U. S. applica- In GreatBritain April 20, 1937 tions S. Nos. 39,289 and 39,290, both filedSeptember 5, 1935.

The staple fibre yarns may be made by any method. Thus they may be madeby forming a roving of staple fibres and converting such roving intoyarn. Preferably, however, the staple fibre yarns are made by theprocesses described in U. S. Patents Nos. 2,077,078 and 2,077,079. Theseprocesses involve causing a bundle of continuous filaments to passbetween two surfaces one of which at least is a cutting surface movingat a speed different from that of the bundle, the other surface servingto press the bundle substantially at a point in its length against thecutting surface. The cutting surface may take the form of a fiutedroller as in U. S. Patent No. 2,077,079, or may be an endless cuttingband as in U. S. Patent No. 2,077,078, and the pressing surface may be astationary surface, or may be a surface, for example a roller, moving atsubstantially the same speed as the cut ting roller or surface as in U;S. Patent No. 2,077,078. It is a characteristic of the processesdescribed in these specifications that the conversion of the bundle ofcontinuous filaments into a staple fibre yarn is effected without at anystage losing the continuity of the bundle as a whole. These processesare therefore referred to as "direct conversion processes.

The shrinkable yarns may be made of any material but it is importantthat the shrinkable yarn associated with a particular staple fibre yarnshould differ in character from the staple fibre yarn so that ontreatment with shrinking agents the shrinkable yarn will shrink, whilstthe staple fibre yarn remains substantially unaffected or at leastshrinks only to a very small extent. This result may be achieved byemploying as the shrinkable yarn a yarn which has a basis of a differentmaterial from the staple fibre yarn and/or which, by reason of itsconstruction, is especially adapted to be shrunk, e. g. a highly twistedcrepe yarn, (i. e., a yarn twisted to such a degree that it possessesthe property of shrinking on treatment with hot 4 Minuteman.

below 50% acetyl content. Or, again, together with staple fibre yarnhaving a basis of cellulose acetate or other organic derivative ofcellulose there may be employed yarn having a basis of a differentderivative of cellulose, of regenerated cellulose, of cellulose acetateor other celluloseester which has been subjected to partial or completesaponification, or yarns of cotton, silk or wool.

Where, on the other hand, the staple fibre yarn has a basis ofregenerated cellulose, the shrinkable yarn may, for example, have abasis of cellulose acetate or other organic derivative of cellulose ormay be a silk or woollen yarn.

Where the yarn which is associated with the staple fibre yarn is ahighly twisted crpe yarn it is not, in general, necessary-that such yarnshould be of different material from the staple fibre yarn, since theordinary aqueous scouring treatments which efi'ect substantial shrinkageof crpe yarns do not efiect any substantial shrinkage of the staplefibre yarns, though where the staple fibre yarns have a basis ofcellulose acetate or other organic derivative of cellulose the treatmentmay crinkle the staple fibres, thus improving their resemblance tonatural woollen fibres. The use of crpe yarns, therefore, presents theadvantage that it is possible by means of them to produce compositeyarns of uniform chemical character. Another way of obtaining compositeyarns which have a uniform chemical character is to employ a staplefibre yarn which is naturally sensitive to shrinking agents and anordinary yarn of the same character,

and to coat the staple fibre yarn 'with areserve, e. g., a gum, wax orstarch, prior to associating such yarns together, so that on subsequenttreatment with a shrinking agent the shrinking agent is prevented by thereserve from acting on the staple fibre yarn. Another process is toassociate with a staple bre yam containing substantially unstretcheuartificial fibres a yarn of the same material which has been stretchedto a substantial extent. In general stretched 'yarns are more sensitiveto shrinking agents than unstretched yarns so that it is possible bycontrolling the conditions to effect substantial shrinkage of thestretched yarn without any substantial effecton the staple fibre yarn.Or, again, staple fibre yarn which contains fibres which have beenshrunk may be associated with an unshrunk yarn of the same material sothat on treatment with a shrinking agent the shrinking effect isrestricted almost entirely to the unshrunk yarn.

It is to be understood, however, that where highly twisted crepe yarnsare employed they are not necessarily made of the same material as thestaple fibre yarns. Thus, very satisfactory results may be obtained byassociating a cellulose acetate staple fibre yarn with a highly twistedviscose crpe yarn or a real silk crepe yarn. Where highly twisted crepeyarns havin a basis of cellulose acetate or other organic derivative ofcellulose are employed they are preferably produced by processes inwhich twist is inserted while the yarn is under the influence of steamor hot water. For such processes reference is made to U. S. Patents Nos.2.088.628, 2,088,587 and 2,089,191.

Where the yarn associated with the staple fibre yarn is a highly twistedcrpe yarn the shrinking may be efiected, as indicated above, by theordinary treatments with aqueous scouring liquids. However, in othercases the choice of shrinking-agent will depend on the character of theyarn to be shrunk. For shrinking cotton 'yarn or yarn having a basis ofregenerated cellulose there may be employed, for example, sulphuric orhydrochloric acid, zinc chloride, thic- 'the shrinkable yarn arepreferably associated together by a doubling twist. In order to obtain afabric in which the composite yarn appears to be composed substantiallyof staple fibre yarn it is preferable that the denier of the staplefibre yarn should exceed substantially the denier of the yarn associatedtherewith. Thus, for example, a 150-200 denier staple fibre yarn may bevery suitably doubled with a 50-100 denier shrinkable yarn. The staplefibre yarn may be permitted to spiral round the shrinkable yarn duringthe doubling operation, for example by leading the staple fibre yarn tothe point where the doubling takes place under a very light tension.Thus, the staple fibre yarn may be fed to the point at which doublingtakes place somewhat faster than the shrinkable yarn in order to obtainthe desired spiralling effect. The staple fibre yam may be fed only.slightly faster, e. g., 5'or faster, or may be fed considerably faster,e. g., 50-100 or 200% or more faster, according to the nature of theproduct desired. If this spiralling effect is effected it is not soimportant that the denier of the staple fibre yarn should substantiallyexceed the denier of the yarn associated therewith.

It will be appreciated that when the yarns are associated by means of adoubling twist the individual component yarns either receive additionaltwist or have some twist removed therefrom, depending on the relativedirections of the doubling twist and the twists in the component yarns.For this reason the twists in the component yarns should be either inexcess of, or short of, that desired for them in the composite yarnproduced. Thus where it is desired to produce a composite yarn in whichthe shrinkable component yarn is a high twist crpe yarn, it is notessential for the yarn fed to the doubling device to be itself a hightwist crpe yarn if, as a result of the addition of the doubling twist,such yarn becomes a high twist crepe yarn in the product. In using hightwist crpe yarns as the shrinkable yarns it is usually preferable toinsert the doubling twist in the same direction as the original twistinsuch yarns so that at no stage have such yarns a twist higher than thatdesired for them in the composite yarns. For example, if an ultimatetwist of 55 turns per inch in the shrinkable yarn of the composite yarnis desired, it is better to feed the yarns having a twist of 50 turnsper inch to the doubling device and increase this to 55 turns per inchby a 5 turns per inch doubling twist in the same direction than to startwith a yarn having an original twist of 60 turns per inch and todecrease this to 55 turns per inch by a doubling twist of 5 turns perinch in the reverse direction.

doubling twist of turns per inch, the doubling the twist in twist beingin the same direction as the viscose yarn; or the product may consist oftwo staple fibre yarns doubled with a single shrinkable yarn, e. g., acomposite yarn produced by feeding two 1'70 denier cellulose acetatestaple fibre yarns (produced as indicated above) and a single 75 denierviscose yarn (hav ing a twist of about 33 turns per inch) to a doublingdevice, the staple fibre yarn being fed 5% faster than the viscose crpeyarn, and inserting a doubling twist of 12 turns per inch in the samedirection as the twist in the viscose yarn.

However, composite ya'ns produced by doubling together staple fibreyarns and shrinkable yarns may themselves be doubled together to formheavier products and/or or may be dou bled with other yarns, e. g.,other shrinkable yarns.

The composite yarns of the invention may be woven into fabrics in anysuitable arrangement. They may, for example, be in the warp or weft orboth in the warp and weft, and in any of these cases may be associatedwith yarns of any other desired character, or composite yarns containinga component having a crpe twist may alternate in the weft and/or warpwith composite yarns containing crpe components of opposite twist. Theinvention is of greatest value in connection with the production ofwoven fabrics but the composite yarns of the present invention may,nevertheless, be formed into fabrics by other fabric-forming operations,for example, by circular knitting or by warp knitting.

The treatment of the composite yarns with a shrinking agent may becarried out prior to, or

subsequent to, the conversion of the yarn into fabric form.

The phrase claims is to be understood having a basis of an organic loseand also yarns having a or regenerated cellulose.

Having described our invention, what we desire to secure by LettersPatent is:

1. Process for the production of composite yarns resembling wool yarns,which comprises associating one or more yarns containing artificialstaple fibres with one or more yarns which, after such association, arecapable of being shrunk relative to such yarns containing artificialstaple fibres, and thereafter shrinking said shrinkable yarns.

2. Composite yarns of a wool-like character containing artificial staplefiber yarns doubled with cellulosic yarns, the artificial staple fiberyarns being uniformly cockled by being present in greater length thansaid cellulosic yarns, and said cellulosic yarns being shrunk to agreater degree than said artificial staple fiber yarns.

3. Composite yarns of a wool-like character containingnftificial staplefiber yarns of an organic derivative of cellulose doubled with othercellulosic yarns, the artificial staple fiber yarns being uniformlycockled by being present in greater length than said other cellulosicyarns, and said other cellulosic yarns being shrunk to a greater degreethan said artificial staple fiber yarns of an organic derivative ofcellulose.

4. Composite yarns of a wool-like character containing artificial staplefibre yarns of cellulose acetate doubled with other cellulosic yarns,the artificial staple fibre yarns being uniformly cockled by beingpresent in greater length than said other cellulosic yarns, and saidother cellulosic yarns being shrunk to a greater degree than saidartificial staple fibre yarns of cellulose acetate.

cellulosic yarns" employed in the as including yarns derivative ofcellubasis of natural ANGUS SMITH BELL. JOSEPH R0 WYLDE.

CERTIFICATE OF CORRECTION.

Patent No. 2,218,655. October 22, 191 0.

ANGUS SMITH BELL, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correctionas follows: Page sec-0nd column, strike out lines 10 to 17, comprising claim 1 and for claims5 and 14. read 1, 2 and 5 respectively, and that the now appearing as 2,

therein that the said Letters Patent should be read with this correctionsame may conform to the record of the case in the Patent Office.

Signed and sealed this 19th day of November, A. D. 191m.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.

